It is common for businesses and homeowners to have a security system for detecting alarm conditions at their premises and signalling these to a monitoring station. One of the primary functions of the monitoring station is to notify a human operator when one or more alarm conditions have been sensed by detectors installed at a monitored premise.
At the premises, an alarm condition may be initially sensed by a detector. Detectors may vary from relatively simple hard-wired detectors, such as door or window contacts to more sophisticated battery operated ones, such as motion and glass break detectors. The detectors may all report to an alarm control panel at the premises. The panel, in turn, may signal the sensed alarm condition to the monitoring station. Personnel at the monitoring station may respond to the signalled alarm condition. They may, for example, call the premises, or dispatch emergency personnel.
Typically, common points of entry and exit at the premises, such as the front, side and rear doors of a premises, are monitored by detectors. At the premises, the alarm system may be armed and disarmed, for example, by entering a numeric or alphanumeric code at a keypad proximate these points of entry. To prevent signalling authorized entries, most alarm systems are programmed to provide an entry delay for events sensed by detectors proximate the keypads. In this way, an authorized entrant is given a reasonable time interval within in which to disarm the alarm system before the monitoring station is notified of an alarm condition.
Unfortunately, unauthorized entrants often exploit this entry delay. They break-in to a premises through a common point of entry and disable the alarm system during the entry delay, by disconnecting, damaging, destroying or otherwise tampering with the control panel, or other infrastructure.
Accordingly, there remains a need for alarm systems and methods that are less susceptible to tampering in the presence of an entry delay interval.